Energy efficiency: delivering the 20% target - COM 2008 772 final

Progress on energy efficiency in Europe The ODEX index measures progress in energy efficiency by major sector (industry, transport, households and services), as well as for all final consumers. For each sector, the index is calculated as a weighted average of sub-sectoral indices of progress in energy efficiency, observed over a given period. Sub-sectors refer to industrial or service sector branches or end-uses for households or transport modes. The sub-sectoral indices are calculated from variations of unit energy consumption indicators, measured in physical units (for instance tons of steel, tonne-km for transport of goods, kWh/appliance, m² for offices, etc.). ODEX provides a better 'proxy' of energy efficiency progress from a policy evaluation viewpoint than the more commonly used monetary indicators.

Progress on energy efficiency in Europe The ODEX index (Figure 1) measures energy efficiency progress by the main sectors (industry, transport and households), as well as for the whole economy (all final consumers). For each sector, the index is calculated as a weighted average of sub-sectoral indices of energy efficiency progress; the sub-sectors are the industrial or service sector branches or end-uses for households or transport modes. The sub-sectoral indices are calculated from variations of unit energy consumption indicators, measured in physical units and selected so as to provide the best “proxy” of energy efficiency progress from a policy evaluation viewpoint. The fact that indices are used enables different units to be combined for a given sector, for instance, for households kWh per appliance, koe/m 2 , tep per dwelling etc. The weight used to get a weighted aggregate is the share of each sub-sector in the total energy consumption of the sub–sectors considered in the calculation. A value of ODEX equal to 90 means a 10 % energy efficiency gain. The variation of the specific consumption of space heating per dwelling linked to building standards is modelled as the change brought about by the introduction of new dwellings with better insulation than the whole stock, since a base year (e.g. 1990), assuming that the unit consumption of new dwellings is equal to the theoretical value implied by thermal regulations (Figure 2). This effect is calculated as follows: ∆UCnew t = (UCnew t * nbrlpn t + ∆UCnew t-1 * (nbrlpr t – nbrlpn t )) / nbrlpr t with: ∆UCnew t=0 = ∆UCnew t=1990 = UC t=1990 nbrlpr t : stock of dwellings at year t nbrlpn t : the volume of construction at year t UC t : unit consumption per dwelling for space heating at year t

Progress on energy efficiency in Europe The ODEX index (Fig.1) measures the energy efficiency progress by main sector (industry, transport, households) and for the whole economy (all final consumers). For each sector, the index is calculated as a weighted average of sub-sectoral indices of energy efficiency progress; sub-sectors being industrial or service sector branches or end-uses for households or transport modes. The sub-sectoral indices are calculated from variations of unit energy consumption indicators, measured in physical units and selected so as to provide the best “proxy” of energy efficiency progress, from a policy evaluation viewpoint. The fact that indices are used enables to combine different units for a given sector, for instance for households kWh/appliance, koe/m2, tep/dwelling… The weight used to get the weighted aggregate is the share of each sub- sector in the total energy consumption of the sub –sectors considered in the calculation. A value of ODEX equal to 90 means a 10% energy efficiency gain. The variation of the specific consumption of space heating per dwelling linked to building standards is modelled as the change brought about by the introduction of new dwellings with a better insulation than the whole stock since a base year (e.g. 1990), assuming that the unit consumption of new dwellings is equal to the theoretical value implied by thermal regulations (Fig.2). This effect is calculated as follow: ∆UCnew t = (UCnew t * nbrlpn t + ∆UCnew t-1 * (nbrlpr t – nbrlpn t )) / nbrlpr t with: ∆UCnew t=0 = ∆UCnew t=1990 = UC t=1990 nbrlpr t : stock of dwellings at year t nbrlpn t : the volume of construction at year t UC t : unit consumption per dwelling for space heating at year t

Energy efficiency and energy consumption in the transport sector Energy efficiency progress (Figure 1) is measured from the ODEX indicator. This index aggregates the unit consumption trends for each transport mode in a single indicator for the whole sector. It is calculated at the level of 8 modes or vehicle types: cars, trucks, light vehicles, motorcycles, buses, total air transport, rail, and water transport. For cars, energy efficiency is measured by the specific consumption, expressed in litre/100km; for the transport of goods (trucks and light vehicles), the unit consumption per ton-km is used, as the main activity is to move goods; for other modes of transport various indicators of unit consumption are used, taking for each mode the most relevant indicator given the statistics available: toe/passenger for air, goe/pass-km for passenger rail, goe/ton-km for transport of goods by rail and water, toe per vehicle for motorcycles and buses. The variation of the weighted index of the unit consumption by mode between t-1 and t is defined as follows It /It -1= 1/( It -1/It) with : energy share EC i (consumption of each mode i in total transport consumption); unit consumption index UC i (ratio : consumption related to traffic or specific consumption in l/100 km for cars); t refers the current year, t-1 to the previous year. The value at year t can be derived from the value at the previous year by reversing the calculation: It /It -1= 1/( It -1/It) ODEX is set at 100 for a reference year and successive values are then derived for each year t by the value of ODEX at year t-1 multiplied by It /It -1. The energy consumption variation of passenger transport in Figure 4 is broken down into 3 explanatory effects: activity effect (increase in traffic), modal shift effect (from private transport to public transport modes) and energy savings (change in specific consumption per unit of traffic). A positive “modal shift effect” means that the share of public passenger transport in passenger traffic is decreasing (shift from public transport to cars) or the road in total freight traffic is increasing (shift from rail-water to road): this offsets energy savings. CO2 emissions for total transport are split into 2 explanatory effects (Figure 6): an activity effect due to an increase in traffic of passengers and freight, CO2 savings due to the reduction in the specific emissions of vehicles per unit of traffic.

Energy efficiency and energy consumption in the household sector Household energy consumption, covers all energy consumed in households for space heating, water heating, cooking and electricity. Figures are reported either aggregated or disaggregated according to the end use categories named and as a total figure or per dwelling or m 2 of housing area. Climate fluctuates from one year to another. When the data is flagged as climate corrected, the data is normalized to reflect similar weather conditions. Consumption in useful energy per degree-day corrects for difference in heating equipment efficiency (which varies according to the fuel uses) and climate. Energy efficiency indices (ODEX) can be defined as a ratio between the actual energy consumption of the sector in year t and the sum of the implied energy consumption from each underlying sub-sector/ end use in year t (based on the unit consumption of the sub-sector with a moving reference year. The evaluation of energy savings in household is carried out at the level of three end uses (heating, water heating and cooking) and five large appliances (refrigerators, freezers, washing machines, dishwashers and TVs). For each end use, the following indicators are used to measure efficiency progress: heating — unit consumption per m 2 per dwelling equivalent to central heating at normal climate; water heating — unit consumption per dwelling with water heating; and cooking — unit consumption per dwelling. The average energy consumption per m 2 per dwelling equivalent to central heating is used to leave out the impact of the diffusion of central heating. The effect of (heating) behaviour was estimated by assuming that technical progress cannot be reversed Household CO 2 -emissions covers the direct CO 2 emitted by fuel combustion.

Energy efficiency and energy consumption in the transport sector Energy efficiency progress (Figure 1) is measured from the ODEX indicator. This index aggregates the unit consumption trends for each transport mode in a single indicator for the whole sector. The energy consumption variation of passenger transport in Figure 5 is broken down into 3 explanatory effects: activity effect (increase in traffic), modal shift effect (from private transport to public transport modes) and energy savings (change in specific consumption per unit of traffic). A positive “modal shift effect” means that the share of public passenger transport in passenger traffic is decreasing (shift from public transport to cars) or the road in total freight traffic is increasing (shift from rail-water to road): this offsets energy savings. CO2 emissions for total transport are split into 2 explanatory effects (Figure 7): an activity effect due to an increase in traffic of passengers and freight, CO2 savings due to the reduction in the specific emissions of vehicles per unit of traffic.

Energy efficiency and energy consumption in the household sector Household energy consumption, covers all energy consumed in households for space heating, water heating, cooking and electricity. Figures are reported either aggregated or disaggregated according to the end use categories named and as a total figure or per dwelling or m2 of housing area. Climate fluctuates from one year to another. When the data is flagged as climate corrected, the data is normalized to reflect similar weather conditions. Consumption in useful energy per degree-day corrects for difference in heating equipment efficiency (which varies according to the fuel uses) and climate. Energy efficiency indices (ODEX) can be defined as a ratio between the actual energy consumption of the sector in year t and the sum of the implied energy consumption from each underlying sub-sector/ end use in year t (based on the unit consumption of the sub-sector with a moving reference year. Household CO2-emissions covers the direct CO2 emitted by fuel combustion.

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